1. Field of the Invention
The present invention relates to pickup devices for agricultural equipment, and the like, wherein a conveyor belt includes material-engaging elements or pickup fingers for picking up hay or grain stalks from the ground.
2. Description of the Prior Art
Pickup devices have been used on agricultural equipment, both on windrowers wherein the pickup device is used to pick up mown hay from the ground, and on combines wherein the pickup device is used to pick up unthreshed grain from windrows on the ground. These pickup devices have included a pair of spaced-apart rollers, an endless conveyor apron circumferentially disposed around the rollers, and a plurality of pickup fingers that are attached to the apron and that project outwardly therefrom.
In U.S. Pat. No. 2,253,797, issued to Melroe, the pickup fingers, which are formed from wire, have a shape which causes the fingers to project outwardly from the conveyor apron as respective ones of the fingers progress around the smaller one of the rollers. The outward movement of the fingers is provided by the shape of the fingers, by the point of attachment of the fingers, and by localized flexing of the belt as the belt wraps around the smaller one of the rollers.
In U.S. Pat. No. 2,385,829, Melroe discloses an improved pickup device in which the rollers each include a V-belt sheave. A V-belt is placed in driving engagement with the sheaves and the conveyor apron is draped circumferentially around both a V-belt and the spaced-apart rollers. Driving engagement between the V-belt and the apron is provided by a plurality of circumferentially spaced-apart rivets which extend from the outer surface of the apron through the inner surface of the V-belt.
This second patent to Melroe also teaches a method for actuating the pickup fingers outwardly. A portion of each finger extends inwardly through respective ones of openings in the apron. Actuation of the fingers outwardly from the apron, when the fingers are proximal to one of the rollers, is achieved by engagement of these inner portions of the fingers with the roller; actuation of the fingers outwardly, when the fingers are intermediate of the rollers, is provided by a metallic structure that is inserted intermediate of the rollers; and actuation of the fingers outwardly, when the fingers pass around another of the rollers, is prevented by providing a plurality of grooves in this second roller for receiving the inner portions of the fingers without actuation thereof outwardly.
In a third patent issued to Melroe, U.S. Pat. No. 2,570,065, a pair of spaced-apart rollers, each including a V-belt shape, are provided as noted in the prior art above. Also, a V-belt is circumferentially disposed around the sheaves as was noted for the previous prior art. The distinctive portion of this reference includes a plurality of narrow and spaced-apart flat belts or conveyor apron portions which are disposed around the rollers and on opposite sides of the V-belt. A plurality of transversely disposed metal slats are then riveted to individual ones of the flat belts and to the V-belt to transmit motion from the V-belt to the individual flat belts. The pickup fingers are secured to respective ones of the metal slats.